Open grid-forming controls for the inverter-based grid

Inverter-based resources now dominate new capacity, but most operate in grid-following mode, injecting current against an external reference instead of establishing one. They often introduce counterintuitive behaviors that are based on opaque proprietary controls and models, and that are foreign to power systems. These unplanned behaviors trigger the conservative one-off EMT studies that turn interconnection into a slow and expensive process.

OpenIBR facilitates better long-term grid planning and is based on three core principles: simplicity, so planning engineers can predict how a plant will behave; grid-forming controls, so that grid behavior mirrors the physics that the grid runs on; and transparency, so it can be verified, not taken on faith.

The library provides an open-source grid-forming controller that emulates a simplified synchronous machine in software. Instead of tracking an external reference, the inverter establishes its own voltage, frequency, and phase, behaving like a well-damped, voltage-forming source. Its tuning parameters are native power-system quantities, so engineers can screen for stability and protection with the analytical tools they already use.

By providing a transparent, validated, and interoperable foundation for inverter behavior, OpenIBR can help resolve long-standing bottlenecks and accelerate the safe integration of inverter-based resources and large electrical loads. Developers, utilities, and regulators can plan around a shared, verifiable design, not a patchwork of proprietary black boxes.